Means for removal and installation of bits in mining and digging machinery

ABSTRACT

Tools for the installation and removal of bits in mining and digging machinery, wherein the bits are characterized by the fact that that portion of the bit body which extends outwardly of the bit mounting means and is engageable by a tool during the extraction process has a smooth, uninterrupted surface free of shoulders, notches, grooves and the like. The tool comprises an elongated handle having thereon a surface capable of administering blows to the cutting end of the tool for installation purposes. One end of the tool has a pivoting assembly affixed thereto which is capable of being placed about the bit body and engaging the bit body in a wedging action when a pulling force is applied to the assembly by the tool handle. The tool handle may be provided with cam surfaces adapted to engage the exterior surface of the bit mounting means and to aid in the application of the pulling force on the pivoted assembly.

United States Patent 1 Krekeler l Nov. 6, 1973 [75] Inventor: Claude B.Krekeler, Cincinnati, Ohio 73] Assignee: The Cincinnati Mine MachineryCo.,

Cincinnati, Ohio [22] Filed: Nov. 16, 1971 [2]] App]. No.: 199,259

Related U.S. Application Data [63] Continuation-impart of Ser. No.842,791, June 30, 1969, Pat. No. 3,622,206, which is acontinuation-in-part of Ser. No.' 753,398, Aug. 19, 1968, abandoned.

3,097,547 7/1963 Krckclcr 254/Ul X Primary Examiner-James L. Jones, Jr.Assistant ExaminerJ. C. Peters Attorney-John W. Melville et al.

'[57] ABSTRACT Tools for the installation and removal of bits in miningand digging machinery, wherein the bits are characterized by the factthat that portion of the bit body which extends outwardly of the bitmounting means and is engageable by a tool during the extraction processhas a smooth, uninterrupted surface free of shoulders, notches, groovesand the like. The tool comprises an elongated handle having thereon asurface capable of administering blows to the cutting end of the toolfor installation purposes. One end of the tool has a pivoting assemblyaffixed thereto which is capable of being placed about the bit body andengaging the bit body in a wedging action when a pulling force isapplied to the assembly by the tool handle. The tool handle may beprovided with cam surfaces adapted to engage the exterior surface of thebit mounting means and to aid in the application of the pulling force onthe pivoted assembly.

15 Claims, l8 Drawing Figures PATENIEDImV 6:913 3.769.683 SHEET 2 BF 6INVENTOR/S MEANS FOR REMOVAL AND INSTALLATION OF BITS IN MINING ANDDIGGING MACHINERY CROSS REFERENCE TO RELATED APPLICATIONS This is acontinuation-in-part of the copending application of the same inventor,Ser. No. 842,791, filed June 30, 1969 and entitled CUTTER BITS AND MEANSFOR MOUNTING THEM (now US. Pat. No. 3,622,206), which, in turn, is acontinuation-in-part of the copending application in the name of thesame inventor, Ser. No. 753,398, filed Aug. 19, 1968 and entitled CUTTERBITS AND MEANS FOR MOUNTING THEM, now abandoned.

BACKGROUND OF THE INVENTION l. Field of the Invention The inventionrelates to tools for the removal and installation of bits in mining anddigging machinery, and more particularly to tools for the removal andinstallation of bits of the type wherein that portion of the bit bodywhich extends outwardly of the bit mounting means and is engageable by atool has a smooth, uninterrupted exterior surface free of shoulders,notches, grooves and the like.

2. Description of the Prior Art In this specification the tools of thepresent invention will be described primarily as applied to the removaland installation of bits of mining machines. It will be understood,however, that the tools of the present invention are equally applicableto similar bits or digger teeth of excavating and earth workingmachinery. Hence, the term bit is intended to encompass digger teeth andthe like.

Prior art workers have devised many forms of bits, digger teeth and thelike. The bits have been of two basic varieties. First, there are thosewhich have elongated body portions adapted to be received in a shankreceiving perforation in a mounting means and are captively andnon-rotatively held therein. A second variety is similarly provided withan elongated body portion adapted to be received and captively held inthe shank receiving perforation of a mounting means. In this instance,however, the elongated body portion is of circular cross section, as isthe shank receiving perforation in the mounting means. The diameter ofthe elongated bit body portion is so dimensioned as to render the bitfreely rotatable within the shank receiving perforation of the mountingmeans. With both varieties of bits, it is necessary to provide aretaining means to assure that the bit will not be removed from theshank receiving perforation of its mounting means during the cuttingoperation. Some retaining means are of the type which must be physicallydisengaged from the bit, the bit then being free to be removed from theshank receiving perforation of its mounting. means by hand or throughthe use of a tool. Sometimes, although the retaining means has beendisengaged from the bit, it is necessary to use a tool to dislodge thebit from its shank receiving perforation. This is true because the bithas become jammed in its shank receiving perforation through the actionof corrosive mine waters, accumulated fines and foreign material, or thelike.

Prior art workers have also devised resilient retaining means, for bothrotatable and non-rotatable bits, which provide a knock-in, pry-outrelationship between the bit and its mounting means. Under suchcircumstances,

a bit may be inserted in the shank receiving perforation of its mountingmeans simply by the application of blows to its cutting end. The bit maybe removed by simply pulling or prying it from its shank receivingperforation with a suitable tool.

Heretofore, bits of both varieties have been characterized by the factthat that portion of the bit body which extends outside the mountingmeans has had thereon a shoulder, notch, groove, or the like, whichcould be engaged by an appropriate prying or pulling tool. Morerecently, however, bits of both varieties have been developed in whichthat portion of the bit body which extends outside the mounting means isfree of shoulders, notches, grooves or the like. Such bits have a numberof advantages. First of all, they can be manufactured more simply andless expensively. Generally, they are formed from bar stock of anysuitable cross sectional configuration. As a consequence, the amount ofmachining required to produce such bits is minimized. In addition, suchbits are stronger and have a greater service life since they have fewerstress raising changes in diameter and in many instances none at all.

Exemplary forms of rotatable bits of the type, just described are taughtin United States Letters Patent Nos. 3,397,012 and 3,397,013. Exemplarytypes of such cutter bits, but of the non-rotatable type, are taught inthe above mentioned US. Pat. No. 3,622,206 of which this application isa continuation-in-part.

Despite their many advantages, such bits have the disadvantage thatthere is no shoulder, notch, groove or the like on that part of theirbody which extends outside their mounting means. As a consequence, it isdifficult (and sometimes impossible) to engage such bits withconventional tools to remove the bits from their mounting means. Thus,while such bits are frequently used with resilient retainers and have aknock-in, pryout relationship with their mounting means, there has beenno tool available to take full advantage of this relationship.

To this end, the present invention is directed to tools for insertingand removing such bits from their mounting means. The tools of thepresent invention are simple and inexpensive to manufacture; requirelittle operating room; are easy to manipulate and are very effective topermit the insertion and removal of such tools with a minimum of effort.

SUMMANY OF THE INVENTION The present invention relates to tools for theremoval and insertion of bits in their mounting means. The bits may beof the rotatable or non-rotatable type. The tools of the presentinvention are particularly adapted for use with bits having a bodyportion extending from their respective mounting means, which bodyportion is free of shoulders, notches, grooves and the like.

The tools of the present invention comprise an elongated handle whichmay have a portion thereon adapted to administer blows to the cuttingend of a bit during insertion of a bit in the shank receivingperforation of mounting means. At one end of the elongated handle thereis a pivoted assembly capable of being placed about that portion of abit which extends outwardly of its mounting means. When a pulling orprying force is exerted on the pivoted assembly by the tool handle, thepivoted assembly will grasp the bit in a wedging action.

In one embodiment, the pivoted assembly of the tool comprises a simpleloop-like structure. In another embodiment, that portion of theloop-like structure which is pivotally affixed to the tool handle isbifurcated with a toothed dog pivotally affixed therebetween. The

tooth dog increases the grip exerted on the bit by the pivotedstructure.

In other embodiments, the end of the tool, bearing the pivotedstructure, is also provided with one or more cam surfaces extendingrearwardly of the pivoted structure and increasing the pulling or pryingforce applied to the pivoted structure by the tool handle. In yetanother embodiment, similar to the embodiments just described, the camsurfaces extend toward the pivoted structure so that the cam surfaceswill lie adjacent the bit axis during the bit removal procedure.

In another embodiment of the tool of the present invention, that end ofthe tool handle bearing the pivoted structure is provided with a headportion having a depression therein adapted to receive the cutting endof the bit. The other end of the tool handle is provided with anenlarged nut. Between the head portion at one end of the handle and theenlarged nut at the other end of the handle there is captively affixedto the handle a sliding hammer capable of administering blows either tothe head portion of the handle or the enlarged nut at the other end ofthe handle. Spring means may be provided to bias the pivoted structureto a position wherein it is out of the way of the depression in the headportion of the tool. During the insertion process, the bit is insertedin the shank receiving perforation of its mounting means and the tool islocated with the cutting end of the bit in the depression in the headportion of the tool. The sliding hammer is then used to administer blowsto the head portion of the tool, driving the bit home in its shankreceiving perforation.

During the extraction process, the pivoted assembly is moved to itsworking position against the force of the above mentioned spring and isplaced about the bit body, the cutting end of the bit extending into thedepression in the head portion of the tool. The spring will tend to holdthe pivoted structure in place on the bit body, freeing one of theoperators hands to manipulate the sliding hammer. The sliding hammer isused to apply blows to the enlarged nut at the opposite end of the toolhandle, thus applying a pulling force of the pivoted structure, causingthe bit to be extracted from the shank receiving perforation of itsmounting means.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view ofan exemplary form of a non-rotating bit and the mounting means therefor.

FIG. 2 is a side elevational view, partly in cross section, illustratingan exemplary form of rotatable bit and the mounting means therefor.

FIG. 3 is a perspective view of a tool of the present invention forinstalling and removing bits of the type shown in FIGS. 1 and 2 into andfrom their respective mounting means.

FIG. 4 is a fragmentary side elevational view of the bit mounting meansassembly of FIG. 1, illustrating (partly in cross section) the tool ofFIG. 3 and its use.

FIG. 5 is a side elevational view and illustrates a modified form of thetool of FIG. 3.

FIG. 6 is a fragmentary perspective view of another embodiment of thetool of the present invention.

FIG. 7 is a fragmentary view of a bitmounting means assembly of FIG. 1illustrating the use of the tool of FIG. 6.

FIG. 8 is a fragmentary perspective view of another embodiment of thetool of the present invention.

FIG. 9 is a fragmentary plan view illustrating yet another embodiment ofthe tool of the present invention.

FIG. 10 is a fragmentary side elevational view (partly in cross section)illustrating a bit-mounting means of the type shown in FIG. 2 and thetool of FIG. 9, as applied thereto.

FIG. 11 is a fragmentary side elevational view of the bit-mounting meansof FIG. 1 and the tool of FIG. 9 as applied thereto.

FIG. 12 is a fragmentary side-elevational view of yet another embodimentof the tool of the present invention.

FIG. 13 is a fragmentary side elevational view of the head portion ofthe tool of FIG. 12, with the pivoted assembly removed.

FIG. 14 is a fragmentary plan view of the head portion of the tool ofFIG. 12.

FIG. 15 is an end elevational view of the tool of FIG. 12, illustratingthe head portion and pivoted assembly thereof.

FIG. 16 is a fragmentary side elevational view illustrating the use ofthe tool of FIG. 12 to insert a bit of trating the use of the tool ofFIG. 12 to extract a bit of the type shown in FIG. 1.

DESCRIPTION OF 'THE PREFERRED EMBODIMENTS FIG. 1 illustrates anexemplary form of bit-mounting means assembly wherein the bit is of thenon-rotatable type, as taught in the above mentioned US. Pat. No.3,622,206 of which the present application is a continuation-in-partapplication. The bit is generally indicated at l and the lug isgenerally indicated at 2. The lug comprises a body 3.

' The body 3 has a shank receiving perforation 4. The axis of the shankreceiving perforation 4 is inclined toward the cutting direction(indicated by arrow A). The angle between the shank receivingperforation axis and the cutting direction may be or less. An angularityof less than 90 (as shown) is generally preferred so that the componentof force tending to shove the bit into the shank receiving perforationis greater and so that the resultant cutting stresses on the bit may bemore nearly in line with the bit axis.

The bit comprises an elongated shank 5 of any suitable cross section.The upper end of the shank terminates in a clearance surface 6 lying atan angle to the shank axis and is relieved on opposite sides (one suchrelief being shown at 7) so as to form a cutting tip 8 having a cuttingsurface 9 substantially parallel to the axis of the shank 5. The bit maybe provided with a hard cutting tip, as shown at 8a in FIGS. 11 and 18.The lower end of the shank 5 terminates in an abutment surface 10 lyingat an angle to the shank axis.

The lug body 3 has a transverse hole 11 extending through the body andintersecting the shank receiving perforation 4. A pin 12 is located inthe hole 11 and may be replaceably held or permanently affixed thereinas by welding or the like. The pin 12 may have a length equal to or lessthan the length of the hole 11. The pin 12 is relieved to form anabutment surface 13 adapted to cooperate with the abutment surface onthe cutter bit. The abutment of surfaces 10 and 13 serve not only todetermine the gauge or depth to which the bit extends into the shankreceiving perforation 4, but also to render the bit non-rotatable byvirtue of the angularity of these abutting surfaces.

FIG. 1 also illustrates an exemplary form of resilient retaining meansfor maintaining the shank 5 in the shank receiving perforation 4. Inthis instance, the inside surface of the perforation 4 has an annularnotch or groove 14 formed therein. The notch 14 is adapted to receiveone or more resilient C-shaped elements of metal or the like. Forpurposes of an exemplary showing, two C-shaped metal elements 15 and 16are illustrated. The elements 15 and 16 are substantially identical.They have an outside diameter greater than the shank receivingperforation but slightly less than the diameter of the annular notch 14.The rings 15 and 16 have an inside diameter slightly less than thediameter of the bit shank 5. In use, the C-shaped elements arecontracted (which can be accomplished by virtue of the fact that theends of each element are spaced from each other) and are shoved into theshank receiving perforation 4 until they reach the annular notch orgroove 14. When the notch 14 is reached, the C-shaped elements arecaptively held in the notch or groove 14.

The bit 1 may be mounted in the mounting means 2 by inserting it intothe shank receiving perforation. Since the diameter of the bit 5 isgreater than the inside diameter of the elements 15 and 16, the bit mustbe forced therethrough. A blow by a tool will be sufficient to cause thebit 1 to assume its proper seated position against the abutment surface13 as shown in FIG. 1. The elements 15 and 16 frictionally engage theshank 5 and prevent removal thereof by centrifugal force or other forcesoperating to remove the bit. During normal cutting conditions, therewill be a large component of force tending to urge the bit toward itsseated position.

Removal of the cutter bit 1 may be accomplished by engaging the exposedportion of the bit by a tool of the present invention and pullingupwardly thereon. Thus, the bit 1 has a knock-in, pry-out relationshipwith its mounting means 2.

FIG. 2 illustrates an exemplary form of rotatable bit and mounting meanstherefor, of the type taught in the above mentioned United StatesLetters Patent Nos. 3,397,012 and 3,397,013. The bit, generallyindicated at 17 and the mounting means, generally indicated at 18, aretypical of the rotatable bitmounting means structure to which the toolsof the present invention are directed.

The bit 17 comprises an elongated body or shank 19 having a circularcross section. At one end, the shank 19 terminates in an abutmentsurface 20. At the other end, the shank 19 terminates in a nose portion21 which may be provided with a hard cutting tip 22. The mounting means18 has a body portion 23 having a forward surface 24 and a rearwardsurface 25. A shank receiving perforation 26 extends between thesurfaces 24 and 25. The mounting means has a rearward extension 27terminating in an upwardly extending anvil portion 28, having thereon anabutment surface 29 adapted to cooperate with the bit abutment surface20. Abutment surfaces and 29 serve to determine the gauge or depth towhich the shank 19 extends into the shank receiving perforation 26.

The diameter of the shank l9 and the diameter of the shank receivingperforation 26 are so sized that the bit 17 is freely rotatable withrespect to its mounting means.

A number of resilient retaining means may be used in such an assembly toprovide a knock-in, pry-out relationship between the bit 17 and itmounting means 18. Since the nature of the resilient retaining meansdoes not constitute a limitation on the present invention, for purposesof explanation, a retaining means of the type taught in United StatesLetters Patent No. 2,965,365 has been illustrated.

The mounting means is provided with a transverse hole 30 intersectingthe shank receiving perforation 26.

The transverse hole contains a resilient holding device comprising ametallic rod 31 encased in a body of resilient substance 32, exceptingupon one side at the portion where the rod traverses the shank receivingperforation 26. The shank 19 of the bit is provided with an annularnotch 33. When the bit 17 is inserted in the shank receiving perforation24 and driven home by blows administered to the cutting end of the bit,the tapered portion 19a of the bit shank 19 will cause the metallic rod31 to be depressed into surrounding body of resilient substance 32 toprovide clearance in the shank receiving perforation 26 for the bitshank 19. When the bit has been driven to its seated position, the notch33 therein will lie adjacent the rod 31 and the rod will be free to snapinto the notch 33 and thus retain the bit in its shank receivingperforation. When a pulling force is applied to bit 17 to remove it fromthe shank receiving perforation 26, the notch is configured to deflectthe rod 31 out of the shank receiving perforation 26, freeing the bitfor removal.

In both of the bit-mounting means assemblies of FIGS. 1 and 2, it willbe apparent that that portion la of bit 1 which extends beyond mountingmeans 2 and that portion 17a of bit 17 which extends beyond mountingmeans 18 are free of shoulders, notches, grooves or the like by whichthe bits 1 or 17 could be engaged by conventional tools. FIG. 3illustrates one embodiment of the tools of the present inventionapplicable to the insertion and removal of bits of the type shown inFIGS. land 2. The tool, generally indicated at 34, comprises a shank orhandle 35. One end of the shank has a head 36 suitably configured toserve as a hammering device for knocking a bit into seated positionwithin its shank receiving perforation. Preferably, the head 36 willcomprise a socket element which contains a material 37 which isrelatively soft when compared with the metal of the bit. In this way,the bit will not be damaged when blows are administered to it by thetool. The material 37 may be of any suitable nature. For example, it cancomprise a body of rolled and compressed leather or rawhide, a body ofsoft metal, a body of resilient rubbery substance, a body of wood or thelike.

The other end of the shank 35 has a ring-like member 38 pivotallyaffixed thereto by means of a pin or the like 39. FIG. 4 more clearlyillustrates the ring 38 and its use-For purposes of an exemplaryshowing, a bitmounting means assembly of the type shown in FIG. 1

is illustrated, and like parts have been given like index numerals.

The ring 38 has an internal diameter slightly larger than the diameterof the bit 1, so that the ring may be readily placed about the bit asillustrated. The ring has a rearwardly extending shank 40 which liesbetween bifurcations 41 and 42 at the end of the tool shank. The pivotpin 39 extends through coaxial perforations in the bifurcations 41 and42 and the ring shank 40. It will be understood by one skilled in theart that it would not constitute a departure from the present inventionto provide the ring 38 with a pair of spaced shanks, adapted to lie oneither side of the end of the tool shank 35 and to be pivotally affixedthereto.

As will be evident from FIG. 4, when an upward pulling force is appliedto the tool shank 35, the pivoted ring 38 will engage the bit portion 1aas at 43 and 44 with a sort of wedging action. Having thus been engaged,the bit 1 can be pulled from the shank receiving perforation of themounting means 2. Since the ring 38 frictionally engages the bit as at43 and 44, the inside edges of the ring should be relatively sharp toensure a better engagement.

In FIG. 5, the tool shank, the ring, the bit and the mounting means aresubstantially identical to that shown in FIG. 4 and like parts have beengiven like index numerals. In this instance however, the bifurcations ofthe tool shank are enlarged (one of which is shown at 42a) so as toprovide a cam surface 45 adapted to cooperate with the top surface 46 ofthe mounting means 2. Removal of the bit 1 is accomplished in the samemanner described with respect to FIG. 4, except that the pulling forceis accomplished by rocking the tool handle on the cam surface 45, thecam surface 45, in turn, rocking on the mounting means surface 46. Iwill be understood by one skilled in the art that the embodiment ofFIGS. 3 and 4 can be used with the bit-mounting means assembly of FIG. 2in the same manner as described. Similarly, the embodiment of FIG. canbe used, the cam surface 45 operating on the front surface 24 of themounting means 18 of FIG. 2.

In FIG. 4 the handle 35 of the tool is shown to the rear of the bit. InFIG. 5 the handle 35 is shown in front of the bit. It will be understoodby one skilled in the art that the tool may be oriented anywhere aboutthe bit where the ring 38 can adequately engage the bit. The embodimentof FIG. 5 is shown in its preferred position because the slope of thebit axis will cooperate with the prying action of the tool.

FIGS. 6 and 7 illustrate another embodiment of the present invention.FIG. 7 shows this embodiment as applied to a bit-mounting means assemblyof the type shown in FIG. 1 (again, like parts have been given likeindex numerals). I

In this instance, a tool shank 47 is shown, equivalent to the tool shank35 in FIG. 3. The bottom end of the shank 47 is reduced in width asindicated at 48. A circular ring 49 is shown, having a pair of spacedrearwardly extending shanks 50 and 51, adapted to be pivotally affixedto the portion 48 of tool shank 47 by a pivot pin or the like 52.

Between the spaced rearwardly extending ring shanks 50 and 51 there ispivotally mounted a dog 53 by means of a pivot pin 54, the ends of whichextend into perforations in the ring shanks 50 and-51. The dog has aseries of teeth 55. When the dog is in the position shown in FIGS. 6 and7, the distance between the dog teeth 55 and the diametrically opposedinside surface of the ring 49 is slightly less than the diameter of thebit 1. Spring means 56 may be engaged on the pivot pin 54 with one end58 engaging the bottom surface of the dog, and the other and 58 engagingthe top surface of the ring shank 50. The spring means 56 will tend topivot the dog upwardly toward a position where the teeth 55 do notextend into the inside opening of the ring 49.

The use of the embodiment of FIGS. 6 and 7 is substantially the same asthat described with respect to FIG. 4. The difference lies in the factthat the bit 1 will be engaged by the ring as at 59 and by the dog teeth55, as illustrated. Such an arrangement is particularly desirable whenthe bit 1 is made of very hard and durable material. Again, the tool maybe oriented anywhere about the bit where the ring 49 and dog teeth 55can adequately engage the bit. 1

It will be understood by one skilled in the art that the reduced portion48 of the tool shank 47 may be provided with configuration similar tothe configuration of the bifurcations in FIG. 5. Thus, a cam surfacewould be presented (as shown in dotted lines at 48a) adapted tocooperate with the upper surface 46 of the mounting means 2.

The embodiment of FIGS. 6 and 7 may be used with a bit-mounting meansassembly of the type shown in FIG. 2. When it is so used, its use willbe identical to that described with respect to FIG. 7.

FIG. 8 illustrates in perspective another type of tool for use withknock-in, pry-out" bits or digger teeth.

The tool of FIG. 8, generally indicated at 60, comprises a handle 61which may have any desired configuration and a bifurcated head portiongenerally indicated at 62. The bifurcations 63 and 64 are spaced fromeach other by a distance substantially equal to or greater than thewidth of the bit to be removed. The bifurcations 63 and 64 are providedwith extensions (one of which is shown at 65) which are adapted toengage a surface on the mounting means and act as cams during thepry-out operation.

A generally U-shaped member 66 is pivotally affixed to the tool head 62by pivot pin 67. The pivot pin extends through coaxial perforations atthe ends of the legs of the U-shaped member 66 and in the bifurcations63 and 64. A central portion 68 of the pin 67 extends between thebifurcations 63 and 64.

The inside surface of the U-shaped member 66 may be provided with two ormore pointed extensions. Two such pointed extensions are shown at 69 and70. The pointed extensions may be made of hardened metal and the likeand appropriately affixed to the U-shaped member 66. Alternatively, thepointed extensions 69 and may be integral with the member 66 and theentire member may be made of hardened material. It will be understoodthat the pointed extensions 69 and 70 generally are directed toward thecentral portion 68 of the pivot pin 67.

The operation of the tool of FIG. 8 may be described as follows. When abit or digger tooth is to be removed from its mounting means, theU-shaped member 66 is placed over the bit and the bit is engaged betweenthe pointed extensions 69 and 70 and the central portion 68 of the pivotpin 67. The tool is so configured as to cause the bit to be engagedrelatively near the forward end of the shank receiving perforation inthe bit mounting means. As the tool handle 61 is moved in the directionof arrow B, the pointed extensions 69 and 70 are caused to dig into thebit body because of the resultant diminishing horizontal distancebetween the pointed extension 69 and 70 and the central portion 68 ofpivot pin 67.

After the pointed extensions 69 and 70 have penetrated the bit shank,continued movement of the tool handle 61 in the direction of arrow Bwill cuase the bit body to be lifted from the shank receivingperforation of the mounting means. The bit body may be removed inincrements, if desired, by performing the above described operations anumber of times. Again, the tool may be oriented about the bit in anyposition where it can get an adequate purchase on the bit and where theextensions 65 on bifurcations 63 and 64 can properly contact themounting means. An approach from the front of the bit (as in FIG. wherepossible, will again put the prying forces more nearly in line with thebit shank axis.

In all of the embodiments shown in FIGS. 5 through 8, the tool shanks orhandles 'may or may not be provided with one or more surfaces capable ofadministering blows to the cutting end of a bit during the bit insertionprocess. The provision of such a pounding surface (as for example, headmeans 36 in the embodiment of FIG. 3) is desirable primarily as a matterof convenience, so that one tool may be used for both the insertion andremoval of the bits. It will further be understood by one skilled in theart that the pivoted assemblies on those tools may have any appropriateconfiguration and may have a central opening which again may be of anyconfiguration. Such configuration is based largely on the crosssectional configuration of the bit to be extracted.

FIGS. 9 through 11 illustrate yet another embodiment of the tool of thepresent invention. In this instance, the tool comprises an elongatedhandle 71. A pair of spaced extensions are affixed to one end of thehandle as by welding or the like. Such extensions are shown at 72 and73. In addition, a socket 74 may be provided for material presenting apounding surface 75. It will be understood that the pounding surface 75may be made up of any of the materials described with respect topounding surfaces 37 in FIG. 3.

The extensions 72 and 73 are spaced by a distance slightly greater thanthe diameter of the bit with which the tool is to be used. In addition,the extensions 72 and 73 are of such length that that portion of the bitextending outside the shank receiving perforation of its mounting meanscan be accommodated therebetween. The free ends of extensions 72 and 73are provided with perforations 76 and 77, respectively, through which apivot pin 78 extends. Those ends of pivot pin 78 which extend beyondextensions 72 and 73 pass through perforations 79 and 80 in the ends ofa U- shaped member 81. Thus, the U-shaped member 81 is pivotally affixedto the free end of extensions 72 and 73. The pivot pin 78 may be held inplace by C-shaped retaining means 82 and 83, of well known type, or byany other suitable means.

The U-shaped element 81 may be provided with a pointed extension 84opposite the central portion of pivot pin 78. While again, the pointedextension 84 may be an integral part of the U-shaped element 81, it isshown as being an insert of carbide or hard metal, let into aperforation 85 in the U-shaped member. It will FIG. 10 illustrates a bitand mounting means of the type shown in FIG. 2, and likeparts have beengiven like index numerals. The Figure illustrates the manner in whichthe tool of FIG. 9 is used to extract bit 17. The U-shaped member 81 islocated about the bit 17 with the lower surface of the U-shaped memberlying against the forward surface 24 of the mounting means 18. The bit17 is therefore located between the pointed extension 84 and the centralportion of pivot pin 78.

As the tool is moved in the direction of arrow C, the cam surface 86aand cam surface 87a (not shown in FIG. 10) will operate on the forwardsurface 24 of the mounting means 18 to apply a pulling force on the U-shaped member 81. At first, the forward portion 17a of the bit shank 19will be gripped in a wedging action between pivot pin 78 and the pointedextension 84, the pointed extension biting into the surface of the bitshank. Thereafter, further movement of the tool in the direction ofarrow C will, through the action of the cam surfaces on the tool and theforward surface 24 of the mounting means, lift or pry the bit 17 fromthe shank receiving perforation 26.

FIG. 11 illustrates the tool of FIG. 9 as applied to the bit-mountingmeans assembly of FIG. 1, again like parta having been given like indexnumerals. In this instance, the U-shaped member 81 is placed about thebit 11 so that the bit is located between the pointed extension 84 andthe pivot pin 78. The U-shaped member 81 rests on the upper surface 46of the mounting means 2. When the tool is pivoted in the direction ofarrow D, the bit 1 will be extracted from the mounting means 2 in thesame manner described with respect to FIG. 10, through the interactionof the tool cam surfaces 86a (not shown) and 87a and the top surface 46of the mounting means 2. While for purposes of an exemplary showing thehandle 73 is illustrated as being to the rear of the bit 1 in FIG. 11,and while the tool will function well in this position, where possibleit may be preferred to locate the handle of the bit at the front of thebit (as in FIG. 5) so that the prying forces will be more nearly in linewith the bit shank axis.

It will be understood by one skilled in the art that the tool of FIGS. 9through 11 has several advantages. First of all, it will be noted thatthe tool cam surfaces 86a and 87a lie adjacent the axis of the bit to beremoved. By virtue of this and the shape of the cam surfaces, a greaterthrow is achieved so that the bit may nonnally be removed by a singleoperation of the tool. In addition, the tool of FIGS. 9 through 11requires less surface on the mounting means with which the tool cammingsurfaces interact. Therefore, if the forward surface 24 of the mountingmeans of FIG. 10 or if the top surface 46 of the mounting means of FIG.11 is relatively small, the tool of FIGS. 9 through 11 can be used togreater advantage than can the embodiments of FIGS. 5 and 8, forexample.

Where the bit axis lies at 90 to the adjacent surface of the mountingmeans (as for example in the bitmounting means assembly of FIG. 10), itwill be understood that the tool may be placed at any orientation aboutthe bit.

FIGS. 12 through 18 illustrate yet another embodiment of the tool of thepresent invention.

The tool comprises an elongated handle or shank 88 having a head member89 affixed to one end thereof and an enlarged nut 90 affixed to theother end thereof. The handle 88 has, captively mounted thereon, asliding hammer 91. The hammer 91 is adapted to apply blows either to thesurface 92 of the head member 89 or to the surface 93 of the nut 90, aswill be explained hereinafter.

As is most clearly shown in FIG. 13, the head member 89 has a forwardsurface 94 having a depression 95 therein, adapted to receive thecutting end of the bit. The head member 89 also has a longitudinal flator relief 96 with a forwardly extending lug 97 permanently affixedthereto. The lug 97 has a perforation 98 extending therethrough.

The perforation 98 is adapted to receive a pivot pin 99. The ends of thepivot pin 99 pass through perforations 100 and 101 in the arms of aU-shaped member 102. Thus, the U-shaped member 102 is pivotally affixedto the forwardly extending lug 97. Again, the pivot pin 99 may be heldin place by C-shaped retaining rings 103 and 104 at its ends, or by anyother suitable means.

The U-shaped member 102 is substantially similar to the member 91 ofFIG. 9. Again, a pointed extension 105 may be provided. The extension105 may be an integral part of the U-shaped member 102 or it may be ahard metal or carbide insert let into a perforation 106 in the U-shapedmember.

A spring 107 may be mounted on pivot pin 99. The spring has one arm 108,the end of which extends into a perforation 109 in the forward face 94of the head member 89. The spring 106 has a second arm 110 which engagesthe top surface of U-shaped member 102, as'shown. The spring 108 servesto bias the U- shaped member to a'position where it lies in abuttingrelationship with the flat 96 on the head member 89. Thus, the U-shapedmember 102 is normally out of the way of the forward surface 94 of thehead member 89 and the depression 95 therein.

FIG. 16 illustrates the use of this tool with the bitmounting meansassembly of FIG. 2 (like parts having been given like index numerals).The tool is shown in the position it will assume during the bitinsertion procedure. The bit 17 is placed in the shank receivingperforation of the mounting means 18 and the tool is placed on the bit,with the bit nose 21 in the depression 95 of the tool head member 89.The operator grasps the tool with one hand and grasps the sliding hammer91 (FIG. 12) on the tool with the other. The operator then causes blowsto be administered by the sliding hammer 91 to the surface 92 of thehead member 89 of the tool. The interaction of the depression 95 in thetool head member and the nose 21 of the bit will cause the bit to beseated in its shank receiving perforation.

FIG. 17 is similar to FIG. 16 and like parts have been given like indexnumerals. FIG. 17 differs from FIG. 16 in that it shows the position ofthe tool during the bit extraction process. In this instance, the tooloperator pivots the U-shaped member 102 in the direction of arrow E andagainst the action of spring 107 (not shown). The U-shaped member 102 isthen placed about the body portion 16a of the bit 17 as shown. This ismade possible by the fact that the nose 21 of the hit is received, inpart at least, in the depression 95 in the head member 89 of the tool.

Since the portion 102 is pivoted in the direction of arrow E against theaction of spring 107, it will tend to maintain the position shown inFIG. 17. Therefore, again the operator is free to grasp the tool withone hand and the sliding hammer thereof with the other. In thisinstance, the operator will use the hammer to administer blows to thesurface 93 of the nut (FIG. 12).

Bit body portion 17a is engaged between forwardly extending lug 97 andthe pointed extension 105. Blows, administered to the surface 93 of thenut 90 will first cause the pointed extension 105 to bite into the bitsurface and then will cause the bit 17 to be removed from the shankreceiving perforation.

FIG. 18 illustrates the use of this tool with the cutter bit-mountingmeans assembly of FIG. 1 (like parts having been given like indexnumerals). In this instance, the head member 89 of the tool is providedwith a depression a in its forward face 94 suitably configured tocooperate with the cutting end of bit 1. Thus, the tool may be used toinsert the bit 1 in the shank receiving perforation of its mountingmeans 2 in a manner identical to that described with respect to FIG. 16.

FIG. 18 illustrates the tool in its position when used to extract bit 1from the shank receiving perforation of mounting means 2. The use of thetool and its operation is identical to that described with respect toFIG. 17.

It will be understood by one skilled in the art that the tool of FIGS.12 through 18 has a number of advantages. First of all, it is compact,easy to use and inexpensive to manufacture. In addition, it does notdepend upon an interaction with any surface on the bit mounting means.The sliding hammer makes the tool positive in its action and enables thetool to insert or extract a bit very rapidly.

Finally, it will be understood by one skilled in the art that theforward surface 94 of the head member 89 of the tool may be providedwith a simple, depression of 'any shape. For example, the depressioncould be cylindrical or rectangular and have the innermost portionthereof filled with material of the type described with respect toelements 37 in FIG. 3. Under these circumstances, the tool could be usedwith a number of different types of bits having differently configuredcutting ends.

Modifications may be made in the invention without departing from thespirit of it. As indicated above, for] example, all embodiments may beprovided with a surface or means suitable to administer blows to the bitduring the bit installation process. Similarly, the various embodimentsof the present invention may have a spring means similar to the spring107 on the embodiment of FIGS. 12 through 18. For example, such a springis shown at 111 in the embodiment of FIG. 8. The spring 11 1 may bemounted on the pivot pin 67 between the bifurcation 74 and the adjacentleg of the U- shaped member 66. One end 111a of the spring is hookedover the last mentioned leg. The other end of the spring 111b isanchored in a perforation in the extension 65. The spring will normallyretain the U- shaped member against the bifurcated head portion 62 in aposition generally indicated at 112. Thus the U- shaped element 66 willbe kept out of the way until needed. The spring 111 will also assist inproperly positioning the U-shaped member 66 and pointed extensions 69and 70 to maintain a grip on the bit, particularly where the bit isremoved in increments.

The embodiments of the invention in which an exclusive property orpriviledge is claimed are defined as follows:

1. A tool for the removal of a bit from the shank receiving perforationof its mounting means wherein the bit is of the type having a bodyportion extending beyond that surface of the mounting means surroundingsaid shank receiving perforation, said bit body portion having a smoothperipheral surface free of shoulders, notches, grooves and the like,said tool comprising an elongated handle with first and second ends,ineans configured to extend about said body portion of said bit, saidmeans having spaced ends pivotally affixed to said first handle end,additional means at said first handle end between said ends of saidpivoted means, said pivoted means and said additional means being sorelated as to engage said bit body portion at at least two places with awedging action when a pulling force is applied to said pivoted means bysaid handle, whereby said bit may be engaged and pulled from said shankreceiving perforation by said tool.

2. The structure claimed in claim 1 including a surface on said handleby which blows may be administered to said bit for installation of saidbit in said shank receiving perforation of said mounting means.

3. The structure claimed in claim 1 wherein said pivoted means comprisesa split ring-like structure, the end of said split ring terminating inspaced rearwardly extending shanks, said shanks being located on eitherside of said first end of said tool handle and being pivotally affixedthereto, a dog comprising said additional means and being pivotallyaffixed at one end between said shanks, the other end of said dog beingtoothed, said split ring having an internal diameter such that said bodyportion of said bit may be received therein, said dog being pivotable toa position wherein said bit body portion when located within said splitring is engaged in a wedging action by said toothed end of said dog andthe diametrically opposed portion of said split ring when a pullingforce is applied to said split ring by said tool handle.

4. The structure claimed in claim 1 wherein said first end of said toolhandle is bifurcated, said pivoted means comprising a U-shaped member,each end of said U-shaped member being pivotally affixed to an adjacentone of said bifurcations by a pivot pin having a central portionextending between said bifurcations and end portions extending throughcoaxial perforations in said bifurcations and the adjacent ends of saidU-shaped member, means to prevent axial movement of said pin, saidcentral portion of said pin comprising said additional means, said bitbody portion being engaged in a wedging action by said central portionof said pin and the diametrically opposed portion of said U-shapedmember when a pulling force is applied to said pin and said U-shapedmember by said handle means, whereby said bit may be extracted from saidshank receiving perforation.

5. The structure claimed in claim 1 wherein said first and second endsof said tool handle are enlarged, the remainder of said handletherebetween being of uniform cross sectional dimension, said firstrendhaving a front surface with a recess therein adapted to receive theforward end of said bit, said first end having a lug thereon comprisingsaid additional means, the front end of said lug extending forwardly ofsaid'front surface, said pivoted means comprising a U-shaped member, theends of said U-shaped member lying on either side of said front end ofsaid lug and being pivotally affixed thereto, said U-shaped member beingswingable between a first position in front of and in a planesubstantially parallel to said front surface of said first end of saidtool handle and a second position along the side of said first'end andin a plane substantially parallel to the axis of said tool handle, ahammer means being captively mounted on said portion of said tool handleof uniform cross sectional dimension and being slidable therealongbetween said first and second enlarged ends, whereby said bit may bepartially inserted in said shank receiving perforation and said firstend or said tool may be placed on said bit with said front end of saidbit in said recess and said U-shaped member in said second position,said bit being driven to its seated position in said shank receivingperforation by blows administered to said first tool end by said hammermeans, and whereby said tool may be placed on said bit when said bit isseated in said shank receiving perforation with said U-shaped member insaid first position and said bit forward end in said recess, said bitbeing engaged in a wedging action by said front end of said lug and adiametrically opposed portion of said U-shaped member and removed fromsaid shank receiving perforation by a pulling force exerted on saidU-shaped member by blows administered to said second tool handle end bysaid hammer means.

6. A tool for the removal ofa bit from the shank receiving perforationof its mounting means wherein the bit is of the type having a bodyportion extending beyond that surface of the mounting means surroundingsaid shank receiving perforation, said bit body portion having a smoothperipheral surface free of shoulders, notches, grooves and the like,said tool comprising an elongated handle with first and second ends, aring-like structure pivotally affixed to said first end of said toolhandle, said ring-like structure having an internal diameter such thatsaid body portion of said bit may be received therein when saidring-like structure lies in a plane normal to the axis of said bit, saidring-like structure lying in a plane other than normal to said bit axisand engaging said body portion of said bit at diametrically oppositepositions when a pulling force is applied to said ring-like structure bysaid tool handle, a cam surface on said first tool end adapted tocooperate with said mounting means surface whereby rocking of saidhandle about said cam surface on said mounting means surface will causesaid tool handle to exert said pulling force.

7. The structure claimed in claim 3 including a cam surface on saidfirst tool end adapted to cooperate with said mounting means surfacewhereby rocking of said handle about said cam surface on said mountingmeans surface will cause said tool handle to exert said pulling force.

8. The structure claimed in claim 4 including means on saiddiametrically opposed portion of said U-shaped member to bite into saidbit body portion during said wedging action.

9. The structure claimed in claim 4 whereineach of said bifurcations hasan extension thereon, a cam surface on each extension, said cam surfacesbeing configured to engage said mounting means surface to one side ofsaid shank receiving perforation therein when said U-shaped member islocated about said bit body portion, whereby rocking of said tool handleabout said cam surfaces .on said mounting means surface will cause saidtool to exert said pulling force.

10. The structure claimed in claim 4 wherein each of said bifurcationshas an extension thereon,-a cam surface on each extension, said camsurfaces being configured to engage said mounting means surface onopposite sides of said shank receiving perforation therein when saidU-shaped member is located about said bit body portion, whereby rockingI of said tool handle about said cam surfaces on said mounting meanssurface will cause said tool handle to exert said pulling force.

11. The structure claimed in claim 4 including a surface on said handleby which blows may be administered to said bit for installation of saidbit in said shank receiving perforation of said mounting means.

12. The structure claimed in claim 4 including means to bias saidpivoted U-shaped member to a position wherein said U-shaped member liesalong said tool handie and rearwardly of said first end whereby saidbiasing means prevents undesired movement of said U- shaped member whensaid member is not in use and augments said wedging action when saidU-shaped member is in use.

13. The structure claimed in claim 5 including means on saiddiametrically opposed portion of said U-shaped member to bite into saidbit body portion during said wedging action.

14. The structure claimed in claim 5 including means to bias saidU-shaped member to said second position whereby said biasing meansprevent undesired movement of said U-shaped member when said member isnot in use and augments said wedging action when said U-shaped member isin use.

15. The structure claimed in claim 5 wherein said portion of said handlebetween said first and second ends is of circular cross section, saidhammer means comprising a cylindrical member having an axial holethrough which said handle portion extends.

1. A tool for the removal of a bit from the shank receiving perforation of its mounting means wherein the bit is of the type having a body portion extending beyond that surface of the mounting means surrounding said shank receiving perforation, said bit body portion having a smooth peripheral surface free of shoulders, notches, grooves and the like, said tool comprising an elongated handle with first and second ends, means configured to extend about said body portion of said bit, said means having spaced ends pivotally affixed to said first handle end, additional means at said first handle end between said ends of said pivoted means, said pivoted means and said additional means being so related as to engage said bit body portion at at least two places with a wedging action when a pulling force is applied to said pivoted means by said handle, whereby said bit may be engaged and pulled from said shank receiving perforation by said tool.
 2. The structuRe claimed in claim 1 including a surface on said handle by which blows may be administered to said bit for installation of said bit in said shank receiving perforation of said mounting means.
 3. The structure claimed in claim 1 wherein said pivoted means comprises a split ring-like structure, the end of said split ring terminating in spaced rearwardly extending shanks, said shanks being located on either side of said first end of said tool handle and being pivotally affixed thereto, a dog comprising said additional means and being pivotally affixed at one end between said shanks, the other end of said dog being toothed, said split ring having an internal diameter such that said body portion of said bit may be received therein, said dog being pivotable to a position wherein said bit body portion when located within said split ring is engaged in a wedging action by said toothed end of said dog and the diametrically opposed portion of said split ring when a pulling force is applied to said split ring by said tool handle.
 4. The structure claimed in claim 1 wherein said first end of said tool handle is bifurcated, said pivoted means comprising a U-shaped member, each end of said U-shaped member being pivotally affixed to an adjacent one of said bifurcations by a pivot pin having a central portion extending between said bifurcations and end portions extending through coaxial perforations in said bifurcations and the adjacent ends of said U-shaped member, means to prevent axial movement of said pin, said central portion of said pin comprising said additional means, said bit body portion being engaged in a wedging action by said central portion of said pin and the diametrically opposed portion of said U-shaped member when a pulling force is applied to said pin and said U-shaped member by said handle means, whereby said bit may be extracted from said shank receiving perforation.
 5. The structure claimed in claim 1 wherein said first and second ends of said tool handle are enlarged, the remainder of said handle therebetween being of uniform cross sectional dimension, said first end having a front surface with a recess therein adapted to receive the forward end of said bit, said first end having a lug thereon comprising said additional means, the front end of said lug extending forwardly of said front surface, said pivoted means comprising a U-shaped member, the ends of said U-shaped member lying on either side of said front end of said lug and being pivotally affixed thereto, said U-shaped member being swingable between a first position in front of and in a plane substantially parallel to said front surface of said first end of said tool handle and a second position along the side of said first end and in a plane substantially parallel to the axis of said tool handle, a hammer means being captively mounted on said portion of said tool handle of uniform cross sectional dimension and being slidable therealong between said first and second enlarged ends, whereby said bit may be partially inserted in said shank receiving perforation and said first end or said tool may be placed on said bit with said front end of said bit in said recess and said U-shaped member in said second position, said bit being driven to its seated position in said shank receiving perforation by blows administered to said first tool end by said hammer means, and whereby said tool may be placed on said bit when said bit is seated in said shank receiving perforation with said U-shaped member in said first position and said bit forward end in said recess, said bit being engaged in a wedging action by said front end of said lug and a diametrically opposed portion of said U-shaped member and removed from said shank receiving perforation by a pulling force exerted on said U-shaped member by blows administered to said second tool handle end by said hammer means.
 6. A tool for the removal of a bit from the shank receiving perforation of its mounting means wherein the bit is of the type having a body portion extending beyond that surface of the mounting means surrounding said shank receiving perforation, said bit body portion having a smooth peripheral surface free of shoulders, notches, grooves and the like, said tool comprising an elongated handle with first and second ends, a ring-like structure pivotally affixed to said first end of said tool handle, said ring-like structure having an internal diameter such that said body portion of said bit may be received therein when said ring-like structure lies in a plane normal to the axis of said bit, said ring-like structure lying in a plane other than normal to said bit axis and engaging said body portion of said bit at diametrically opposite positions when a pulling force is applied to said ring-like structure by said tool handle, a cam surface on said first tool end adapted to cooperate with said mounting means surface whereby rocking of said handle about said cam surface on said mounting means surface will cause said tool handle to exert said pulling force.
 7. The structure claimed in claim 3 including a cam surface on said first tool end adapted to cooperate with said mounting means surface whereby rocking of said handle about said cam surface on said mounting means surface will cause said tool handle to exert said pulling force.
 8. The structure claimed in claim 4 including means on said diametrically opposed portion of said U-shaped member to bite into said bit body portion during said wedging action.
 9. The structure claimed in claim 4 wherein each of said bifurcations has an extension thereon, a cam surface on each extension, said cam surfaces being configured to engage said mounting means surface to one side of said shank receiving perforation therein when said U-shaped member is located about said bit body portion, whereby rocking of said tool handle about said cam surfaces on said mounting means surface will cause said tool to exert said pulling force.
 10. The structure claimed in claim 4 wherein each of said bifurcations has an extension thereon, a cam surface on each extension, said cam surfaces being configured to engage said mounting means surface on opposite sides of said shank receiving perforation therein when said U-shaped member is located about said bit body portion, whereby rocking of said tool handle about said cam surfaces on said mounting means surface will cause said tool handle to exert said pulling force.
 11. The structure claimed in claim 4 including a surface on said handle by which blows may be administered to said bit for installation of said bit in said shank receiving perforation of said mounting means.
 12. The structure claimed in claim 4 including means to bias said pivoted U-shaped member to a position wherein said U-shaped member lies along said tool handle and rearwardly of said first end whereby said biasing means prevents undesired movement of said U-shaped member when said member is not in use and augments said wedging action when said U-shaped member is in use.
 13. The structure claimed in claim 5 including means on said diametrically opposed portion of said U-shaped member to bite into said bit body portion during said wedging action.
 14. The structure claimed in claim 5 including means to bias said U-shaped member to said second position whereby said biasing means prevent undesired movement of said U-shaped member when said member is not in use and augments said wedging action when said U-shaped member is in use.
 15. The structure claimed in claim 5 wherein said portion of said handle between said first and second ends is of circular cross section, said hammer means comprising a cylindrical member having an axial hole through which said handle portion extends. 